gno/usr.man/man2/alarm.2
1997-10-04 04:40:10 +00:00

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.\" @(#)alarm.3 8.2 (Berkeley) 4/19/94
.\"
.TH ALARM 2 "16 January 1997" GNO "System Calls"
.SH NAME
.BR alarm
\- set signal timer alarm
.SH SYNOPSIS
.br
#include <unistd.h>
.sp 1
long
\fBalarm\fR (long \fIseconds\fR);
.br
long
\fBalarm10\fR (long \fItenths\fR);
.SH DESCRIPTION
.LP
The
.BR alarm
function
waits a count of
.BR seconds
before asserting the terminating signal
.BR SIGALRM .
When the signal has successfully been caught,
.BR alarm
returns the amount of time left on the clock.
.LP
If an alarm has been set with
.BR alarm ,
another call to
.BR alarm
will supersede the prior call.
If
.IR seconds
is zero, the alarm timer is disabled.
.LP
.BR alarm10
is identical to
.BR alarm ,
except that values are measured in tenths of seconds.
.SH ERRORS
No errors are possible.
.SH STANDARDS
.BR alarm
is not quite POSIX conformant in that it uses types of
.BR long
rather than
.BR "unsigned int" .
.BR alarm10
is a non-standard function.
.SH SEE ALSO
.BR setitimer (2),
.BR sigpause (2),
.BR sigvec (2),
.BR signal (2),
.BR sleep (3),
.BR ualarm (3),
.BR usleep (3)
.SH HISTORY
An
.BR alarm
function appeared in Version 7 AT&T UNIX.